Method for sending compressed data representing a digital image and corresponding device

Abstract

A method for sending compressed data representing at least part of a digital image includes the following steps: encoding ( 220 ) source data representing said part to obtain first compressed data having a given size; based at least on said size, including ( 210 ) said first compressed data either in a first slice comprising second compressed data representing other parts of the digital image or in an empty second slice; sending the slice comprising said first compressed data. A corresponding device is also described.

The invention claimed is: 
     
       1. Method for sending compressed data representing at least part of a digital image, comprising:
 encoding source data representing the part to obtain first compressed data having a first complexity; 
 including the first compressed data in a selected one of either a first slice and an empty second slice, wherein the first slice comprises second compressed data representing other parts of the digital image and having a second complexity, and wherein the selection of one of the first slice and the second slice depends on at least the first complexity and the second complexity; and 
 sending the slice comprising the first compressed data, 
 wherein at least one of the encoding, the including, and the sending is performed by at least one computer processor. 
 
     
     
       2. Sending method according to  claim 1 , wherein the source data is encoded according to a coding parameter adapted to influence size of the encoded source data and determined depending on a volume of the second compressed data. 
     
     
       3. Sending method according to  claim 2 , wherein the coding parameter is a quantization parameter and is determined depending on a size of the second compressed data compared to a predetermined average size associated with the other parts. 
     
     
       4. Sending method according to  claim 2  or  3 , wherein, if the first compressed data are included in an empty second slice, the first slice is completed by padding data. 
     
     
       5. Sending method according to  claim 4 , wherein the coding parameter is a quantization parameter and wherein, with respect to a sum of the volume of the second compressed data and an expected volume of an expected remaining number of the other parts, the coding parameter is increased if the sum is greater than a slice budget. 
     
     
       6. Sending method according to  claim 1 , wherein, if the first compressed data are included in the empty second slice, the first slice is completed by padding data. 
     
     
       7. Sending method according to  claim 1 , wherein the selection of one of the first slice and the second slice for inclusion therein of the first compressed data is also based on a predetermined maximum number of represented parts per slice. 
     
     
       8. Sending method according to  claim 1 , wherein the first compressed data is included in the second slice if sizes of the first compressed data and second compressed data exceed a predetermined maximum slice size. 
     
     
       9. Sending method according to  claim 1 , wherein the selection of one of the first slice and the second slice for inclusion therein of the first compressed data further depends on an amount of compressed data representing at least one part among the other parts. 
     
     
       10. Sending method according to  claim 1 , wherein the first compressed data is included either in the first slice or in the second slice further depending on a quantization value used for encoding the source data. 
     
     
       11. Sending method according to  claim 1 , wherein the selection of one of the first slice and the second slice for inclusion therein of the first compressed data further depends on a quality of representation of the source data by the compressed data. 
     
     
       12. Sending method according to  claim 1 , wherein the first compressed data are encoded according to a first level encoding pass enabling the first compressed data to be obtained within a determined time period, and wherein the method further comprises:
 a second encoding step for generating third compressed data representing the part, according to at least one second level encoding pass; and 
 a step of selecting the third compressed data instead of the first compressed data for being included in said including step, on at least one condition, comprising that the third compressed data is obtained within the determined time period. 
 
     
     
       13. Sending method according to  claim 12 , further comprising a step of including a further image part in either one of the first slice and the second slice depending on at least a size of the third compressed data. 
     
     
       14. Computer program stored on computer-readable information storage means and comprising instructions for carrying out each step of the method according to  claim 1  when the program is loaded and executed by a programmable apparatus. 
     
     
       15. Computer-readable information storage means readable by a computer or a microprocessor and storing computer program instructions for carrying out each step of the method according to  claim 1  when the program is loaded and executed by a programmable apparatus. 
     
     
       16. Sending method according to  claim 1 , wherein the sending method is performed by one or more processors executing stored computer program instructions. 
     
     
       17. Device for sending compressed data representing at least part of a digital image, comprising:
 means for encoding source data representing the part into first compressed data having a first complexity; 
 means for including the first compressed data in a selected one of either a first slice and an empty second slice, wherein the first slice comprises second compressed data representing other parts of the digital image and having a second complexity, and wherein the selection of one of the first slice and the second slice depends on at least the first complexity and the second complexity; and 
 means for sending the slice comprising the first compressed data.